Background: Long-term oral dasatinib administration can induce pulmonary arterial hypertension (PAH) in pediatric patients with Philadelphia chromosome-positive (Ph ⁺) acute lymphoblastic leukemia (ALL). We describe the findings in two pediatric cases involving Ph ⁺ ALL patients who developed cardiovascular events such as PAH after dasatinib treatment, and present a review of the related literature. Case presentation: Two pediatric patients diagnosed with B-cell ALL ( BCR-ABL P190 fusion gene positive) received conventional chemotherapy and imatinib simultaneously, which was then changed to dasatinib because of a partial response. The two patients developed PAH after 18 months and 6 years of dasatinib therapy. All signs and symptoms improved after immediate discontinuation of dasatinib and symptomatic treatment. Conclusions: Pediatric Ph ⁺ ALL patients receiving dasatinib should be carefully monitored for serious cardiopulmonary and vascular events such as PAH. Development of adverse reactions should be followed by immediate and permanent discontinuation of oral dasatinib. Dynamic monitoring by echocardiography is recommended when administering dasatinib for maintenance therapy.